NF-κB Signaling in Macrophages: Dynamics, Crosstalk, and Signal Integration

The nuclear factor-kappa B (NF-kappa B) signaling pathway is one of the best understood immune-related pathways thanks to almost four decades of intense research. NF-kappa B signaling is activated by numerous discrete stimuli and is a master regulator of the inflammatory response to pathogens and cancerous cells, as well as a key regulator of autoimmune diseases. In this regard, the role of NF-kappa B signaling in immunity is not unlike that of the macrophage. The dynamics by which NF-kappa B proteins shuttle between the cytoplasm and the nucleus to initiate transcription have been studied rigorously in fibroblasts and other non-hematopoietic cells, but many questions remain as to how current models of NF-kappa B signaling and dynamics can be translated to innate immune cells such as macrophages. In this review, we will present recent research on the dynamics of NF-kappa B signaling and focus especially on how these dynamics vary in different cell types, while discussing why these characteristics may be important. We will end by looking ahead to how new techniques and technologies should allow us to analyze these signaling processes with greater clarity, bringing us closer to a more complete understanding of inflammatory transcription factor dynamics and how different cellular contexts might allow for appropriate control of innate immune responses.